The requirements on the lock from the people are higher and higher, as the improvement of the living standard.
The existing cathode locks implement the locking process or unlocking process by utilizing the lock tongue to push the lock catch. In many occasions, for example technology department, the doors are required to be in a closed state mostly for keeping the door in a normally-closed state; but during a particular time period, for example the decoration decoration period, the doors are required to be open more oftenly for facilitating the passing of the decorate personnel, further the locks are required to be in the normally-opened state. In the passway of the public space (for example the cinema and so on), the doors are required to be in the normally-closed state during the non-business hours, while the doors are required to be in the normally-opened state during the business hours. However, the door locks are not able to meet the free switch between the normally-opened state and the normally-closed state; thereby there is a need to design different types of locks, which will surely increase the cost of the production.